I have a 2009 F150 ext. cab 4x4 with the 4.6. The truck came stock with the P-rated (Hankook Dynapro) tires and the pressures on the door say 35psi. The new LT265/70r17 goodyear wrangler territorries are a load range E tire. what should the new tire pressures be set too? I have them at the max 80 psi now but have a feeling it is too much. My grandfather said to try around 45psi.